Risk estimation and prediction by modeling the transmission of the novel coronavirus (COVID-19) in mainland China excluding Hubei province

Hui Wan; Jing-an Cui; Guo-Jing Yang

In this paper, we proposed a novel COVID-19 transmission model incorporating the intervention measures implemented in China. Particularly, we adopted two novel function forms which dynamically captured the real-time endemic situation. The first one is the contact rate, c(t), which was assumed to be dependent on the cumulative number of confirmed cases to better quantify the varied interventions and self-protection measures. The other one is the contact tracing rate, which was dependent on the number of new cases. We evaluated the impact of partial lifting control measures on COVID-19 transmission. Our results show that relieve self-protection too early may lead to the spread of the virus for a longer time and more people would be infected, and may even lead to the mass transmission of the virus again. The reduction of the emergency response level does not mean that people can be off guard. At least until the end of March, life will not be able to return to normal.